If the plant is horribly pot-bound, you could pot up, but that should be into a soil very similar to the soil it's in now. Wait until just before the plant wakes in spring to bare-root and repot into new soil. You should avoid repotting deciduous plants when they are in leaf, except in extreme emergency.

Good luck. ;o)

Al

Thank you Al for the reply. It's not an emergency, so I will wait.
What do you think about the soil mix? Maybe you have better proposition for the roses? Anyway, as I wrote, I can not get any turface here. The keramzyt is probably a worse water absorbent than turface. It's less porous. I think it's something you call oildri. The material is used for insulation against cold too.

It's difficult to assess how appropriate the keramzyt might be w/o seeing it. If the particles are mostly from 1.5 mm - 3.5 mm, it's stable and used as an absorbent, it should work well in soils. I'll wish you very good luck - will you let me know how you fare?

Al